Low density, open, lofty and resilient nonwoven surface treating products have been widely used for cleaning, buffing and polishing objects such as cooking utensils, kitchen appliances, household fixtures, walls and floors. Nonwoven products suitable for these purposes have been made according to the teachings of Hoover et al. in U.S. Pat. No. 2,958,593 and McAvoy in U.S. Pat. No. 3,537,121, and have found wide acceptance for both industrial and home use.
Typically, these nonwoven cleaning, buffing and polishing products are formed of an open, lofty, nonwoven matrix of crimped, synthetic, organic staple fibers which are bonded together at points where they contact one another. Generally, resinous binders are used, and often these contain fillers, pigments and abrasive particles.
The resinous binders currently being used in the manufacture of such products typically are applied as either aqueous or organic solvent solutions. However, with the increasing concern for environmental quality, employee safety, and costs, organic solvent based systems have become less acceptable. Furthermore, high water content binder systems generally require more energy to cure than organic solvent based systems and are also less than desirable. Aside from these considerations, the choice of binder has also been largely controlled by the type of fibers used to form the matrix.
Polyester staple fibers, even though significantly less expensive than nylon staple fibers, have not been universally accepted for use in the nonwoven matrix of these cleaning, buffing and polishing products because of the limited adherence of many of the commonly used binder resins to polyester. For example, phenol formaldehyde resins, which have been widely used to bond nylon fiber matrices in nonwoven abrasive and polishing products, typically have not been used as the primary binder for polyester fiber matrices because the cured resin does not adhere well to polyester. Although polyester nonwoven abrasive products bonded with a phenol formaldehyde binder resin have an excellent initial appearance after fabrication, they typically shed resin and fibers, and become excessively thinned and limp shortly after the commencement of their use in cleaning or polishing applications. Furthermore, when water based latex binders have been used as binders for polyester nonwoven matrices, the resultant products are limited in their field of useful applications as these binders have poor resistance to chemical cleaners and the like. Therefore, to be used successfully in such cleaning, buffing and polishing articles, polyester fibers have generally required a more costly, organic solvent based resinous binder.
One significant commercial application for the nonwoven cleaning, buffing and polishing products described above is in the polishing pads used with floor polishing machines However, the advent of ultra high speed floor polishing machines, which operate at a polishing pad speed ranging from about 1000 to about 3200 revolutions per minute, have placed new demands upon the performance of nonwoven floor polishing pads. So too has the requirement that polish coated floors have a gloss level which gives the optical illusion that the floor is wet or has the "wet look". In order to meet these demands a floor polishing pad must, in addition to cleaning the floor of lightly adhered soil, quickly buff the polish coated floor to a high luster without imparting swirl marks. Furthermore, when in use, the pad must not transfer or smear onto the floor, or experience excessive drag causing the floor polishing machine to operate at a lower speed and become overloaded.